The overall objective of this study is to determine the efficacy of various classes of pharmacological anti-inflammatory agents in limiting the formation of edema in burn wounds. To this end, a dual experimental modality is being followed in which procedures for the treatment of burns are evaluated in vivo in both microscopic tissue models and whole animal systems. Extensive experimental data we have acquired indicates there is a direct correlation between the severity of thermal insult to tissue and the inhibition of diffusive macromolecular transport in the interstitial matrix. We have developed a technique to quantify the physiological state of tissue as characterized by its measured diffusivity based on determination of the time dependent concentration profile of the macromolecule being transported. Experimental data obtained from computer analysis of photomicrographs of the extravasation process is compared with an analytical transport model to identify values for the diffusivity. The data we have obtained is quite significant. We have identified and measured a basic change in physiological function, as characterized by the interstitial macromolecular diffusivity, in direct proportion to the severity of thermal insult. Very consistent results have been observed for both freezing and burning protocols. Control values are matched quite well, and thermal injury is seen to produce a progressive reduction in diffusivity with increasing severity.